Manufacture of rivets.



No. 820,586. PATENTED MAY 15, 1903.

N. MARSHALL.

MANUFACTURE OF RIVBTS.

IIIIIIIIIIIIIIIII 0'1. 2a. 1903.

WASSW a Hill-W mn m UNITED STATES PATENT OFFICE.

No. scopes.

Specification of Letters Patent.

Patented May 15, 1906.

Application filed October 28, 1998 Serial In. 178.459.

To all whom it may concern:

Be it known that I, N ORMAN MARSHALL, of Newton in the county of Middlesex and State oi Massachusetts, have invented certain new and useful Improvements in Manufacture of Rivets, of which the following is a specification.

The invention relates to the manufacture of rivets on metal plates; and its object is to provide rivets which may be economicall made and by which other parts maybe e fectively and conveniently riveted to the metal plates. The invention may be used with especial advantage in riveting together small parts made from sheet metal-such, for instance, as various parts of incandescentlamp sockets and other small electrical appliances, although not confined to such use.

Heretofore it has been customs. to connect such parts with screws or Yy rivets passed through holes in the connected parts, as in the usual manner of riveting parts toether. In practicing the present invention form an integral rivet ,on one of the plates or arts to be connected together by causing a fi dw of the metal from one side of the plate toward and out from the op osite side of the plate and shaping the out owin metal to 've the rivet the desired form. he lateral ow of the metal at the point in the late where the rivet is to be formed is pro need by a die which is forced into the side of the ate ow to that on which the rivet is to he formed, and the shape of the rivet is determined by an oppositely-arranged die into which the metal is forced. I have discovcred that by properly shaping and proportioning the'forcing or male die the metal of the plate may be caused to flow laterally into the shaping or female die without disrupting or separating the metal from the plate. The exact shape and the proportions of the male die re uislte for the proper results will vary somew at with the shape and size of the rivet to be produced and with the thickness and composition of the plate. The die should be so 8 speed and proportioned that the lateral and forward ressure exerted by the die on the metal wili be distributed in such'manner as to cause a forward flow of the metal as the die enters the plate and not pierce or disru t the late. To this end the sides of the is she d converge to a blunt or rounded point, the inclination or curve of the sides and the shape of the point depending within narrow limits on the thickness and composition of the plate and the size and shape of the rivet to he formed thereon.

flhe invention will be more fully under- ,stood from an explanation, in connection with the accompan drawings, in which- If e 1 is a section through a plate on which a rivet has been formed in accordance with my invention. Fig. 2 is a plan view of the same. Fig. 3 is a sectional view showing the dies which I prefer to employ in practicing the invention, and Figs. 4, 5, and 6 are views of parts secured by rivets formed in accordance with my invention.

In Figs. 1, 2, and 3 a metallic plate A of sheet metal, such as is used in the menu acture of the parts of electric-lamp sockets switches, &c., is shown upon an enlarged scale the better to illustrate the present invention.

The plate A has formed thereon one or more into 9.1 rivets a, which, as shown, are 'cylindrica in shape. This integral rivet is formed by sub'ectmg the plate to pressure between 8. male die B and a female die C. The femaleshap' -die 0 is cylindrical to correspond to the she e of the rivet, while the male forcing-die as a cone-like form with blunted or curved end b and curved converging sides I), substantially as indicated in Fig. 3. I have found that a male die of substantially the form-shown will cause a forward flow of the metal as the die enters the plate, so that the metal is upset from the op osite side of the plate. As this metal is ihrced forward and out from the side of the plate by the male die it enters the female die and assumes the shape of such die, thus forming the rivet. Integral rivets may thus be ,quickly and cheaply formed which will form a more secure and efiicient connection for other parts than independent rivets. The use of such rivets also facilitates the assembling of the parts, reduces the number of parts to be handied and the operations to be performed, with aresulting re notion in the cost of manufacture.

In the manufacture of small parts, such as used .in electric-lighting fixtures, the invention is especiallyvalnab e, and its a lication to some of such devices is shown in igs. 4, 5, and 6. T In Fi 4 the rivet a is formed on a sheet-metal place A and is usedin connecting the piece D thereto, the parts forming a contact for Westinghouse lamps In Fig. 5 the rivet a is formed on a strip A and connects a switch-contact E thereto. In Fig. 6

two rivets a are formed on a piece A, which forms the frame for a socket-key F, and these rivets secure the spring contact-strip G to the frame.

If it is desired to form a rivet with a flat upper end, this may be done by mounting a p unger C in the female die, which bears upon the metal as it is upset and tends to keep it flat at the end.

I refer to provide the male die with a shou der B for limit' the entrance of the die into theplate A an .also to press on the plate about the cavity formed b the die B and prevent any distortion of t e plate at this oint.

at I claim, and desire to secure by Letters Patent, is-

1 A metal plate provided with an integral imperforate cylindrical rivet on one side and a conical-she ed recess on the opposite side from which t e metal has flowed to form the rivet, substantially as described.

2. A metal plate provided with an integral lmperforate rivet on one side and a recess on the opposite side, the cross-sectional area of whlch adually increases from the surface of thep ate toward the rivet and from which the metal has been forced outwardly and laterally to form the rivet, substantially as described.

In testimony whereof I have aflixed my signature in presence of two witnesses.

NORMAN MARSHALL. Witnesses: I

O. A. SANDERS. IRA L. FISH. 

